1321201240 has 32 divisors (see below), whose sum is σ = 3147569280. Its totient is φ = 497393152.

The previous prime is 1321201237. The next prime is 1321201241. The reversal of 1321201240 is 421021231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321201241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 970792 + ... + 972151.

It is an arithmetic number, because the mean of its divisors is an integer number (98361540).

Almost surely, 2^1321201240 is an apocalyptic number.

1321201240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321201240 is an abundant number, since it is smaller than the sum of its proper divisors (1826368040).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1321201240 is a wasteful number, since it uses less digits than its factorization.

1321201240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1942971 (or 1942967 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 1321201240 is about 36348.3320112492. The cubic root of 1321201240 is about 1097.2939656094.

Adding to 1321201240 its reverse (421021231), we get a palindrome (1742222471).

Subtracting from 1321201240 its reverse (421021231), we obtain a square (900180009 = 30003²).

The spelling of 1321201240 in words is "one billion, three hundred twenty-one million, two hundred one thousand, two hundred forty".